Eczema is an itchy and red skin condition, which may affect 20% of people world wide at some time in their life. Though it may improve with age, there is no cure. Many children outgrow this disorder as they reach secondary school age. Constant itch makes life uncomfortable for those with this condition, no matter what age they are.
Conventional medical treatments make life better for people; however, some people who do not see an adequate improvement in their eczema or fear side-effects of conventional medical products, turn to complementary alternatives to conventional medical treatment. This review is of two such products: evening primrose oil (EPO) and borage oil (BO) taken orally (by mouth), which have been thought to have benefits for eczema.
We included 27 studies, with 1596 adults and children from 12 countries. Of these, 19 studies compared EPO with a placebo (dummy) treatment, and 8 used BO compared with placebo. We looked for evidence of overall improvement in eczema and in quality of life. All 27 studies evaluated overall improvement of eczema, but only 2 studies of EPO measured improvement in quality of life. There was no statistically significant advantage demonstrated for either EPO or BO compared to placebo. In summary, we did not find evidence that eczema improved by taking these products any more than it did by taking placebo.
There was some evidence of mild and temporary side-effects for participants with either product or placebo, which were mainly mild, and included temporary headache and upset stomach or diarrhoea. With EPO there is an anticoagulant (blood-thinning) effect when taking these products. There is a warning with the blood thinner warfarin (Coumadin®) that taking EPO can increase bleeding. One report warns that if EPO is taken for a prolonged period of time (more than one year), there is a potential risk of inflammation, thrombosis, and immunosuppression due to slow accumulation of EPO in the tissues. Another reports a single case in which EPO was thought to have produced harms. We found no clinical evidence of such harm in these short-term trials.
This systematic review found no evidence that either BO or EPO are effective in treatment of eczema. Both of these products and the placebos used in the studies had similar mild, temporary side-effects, which were mainly gastrointestinal.